Direct lipid profiling of single cells from inkjet printed microarrays

The on-demand printing of living cells using inkjet

technologies has recently been demonstrated and allows for the controlled

deposition of cells in microarrays. Here, we show that such arrays can be

interrogated directly by robot-controlled liquid microextraction coupled with

chip-based nanoelectospray mass spectrometry. Such automated analyses

generate a profile of abundant membrane lipids that are characteristic of cell

type. Significantly, the spatial control in both deposition and extraction steps

combined with the sensitivity of the mass spectrometric detection allows for

robust molecular profiling of individual cells.